Lagunitas [Lomitos Cgl, Talara Fm] (Eocene of Peru)

Where: Piura, Peru (4.7° S, 81.3° W: paleocoordinates 12.6° S, 109.9° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Lomitos Conglomerate Member (Talara Formation), Bartonian (41.3 - 38.0 Ma)

• Regarded as lower Upper Eocene on the basis of faunal similarity. Foraminifera suggest an upper Eocene age. Olsson states that the Talara and Saman rocks can be referred to the Upper Eocene and in terms of the European section, to the Bartonian and Ludian.....respectively? In most places the Talara Formation can be divided into three members, a lower shale (Talara Shale), a middle sandstone (Talara Sandstone), and an upper shale (Pozo Shale). In a complete section the Talara Formation has an average thickness of about 2800 ft. The collection is derived from a sandy basal layer known as the Lomitos Conglomerate in the Talara Shale member, which can reach a thickness of 400 ft or more. From a zone of coarse, black, quartzitic cobbles in arenaceous shales, resting upon eroded Restin shales.

• group of beds-level stratigraphic resolution

Environment/lithology: coastal; poorly lithified, coarse-grained, pebbly, black, sandy shale

• Appears to be shelfal siliciclastic environment judging from faunal composition.
• Coarse, black, quartzitic cobbles in arenaceous shales

Size class: macrofossils

Collection methods: quarrying,

• No museum repositories are reported, but material may presumably be the AMNH of PRI collections. Because of uncertaintly this field is left ommited.

Primary reference: A. A. Olsson. 1930. Contributions to the Tertiary Paleontology of Northern Peru: Part 3, Eocene Mollusca. Bulletins of American Paleontology 17(62):1-164 [A. Miller/A. Hendy/A. Hendy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 52528: authorized by Austin Hendy, entered by Austin Hendy on 10.08.2005

Creative Commons license: CC BY (attribution)

Taxonomic list

• Exhaustive for Mollusca.
 Nummulitacea - Discocyclinidae
 Terebratulida - Terebratulidae
 Carditida - Carditidae
Venericardia sp. Lamarck 1801 clam
 Cardiida - Cardiidae
Cardium sp. Linnaeus 1758 cockle
 Poromyida - Verticordiidae
Verticordia sp. Sowerby 1844 clam
 Ptenoglossa - Epitoniidae
"Epitonium (Acrilla) paytens n. sp." = Acrilla, Epitonium (Acrilla) peruvianum
"Epitonium (Acrilla) paytens n. sp." = Acrilla wentletrap
Epitonium (Acrilla) peruvianum Olsson 1928 wentletrap
 Neogastropoda - Olivellidae
Agaronia saxosa Olsson 1928 snail
 Neogastropoda - Buccinidae
 Neogastropoda - Melongenidae
 Neogastropoda - Volutidae
 Neogastropoda - Harpidae
 Neogastropoda -
 Cypraeoidea - Cypraeidae
"Cypraea boggsi" = Cypraeorbis boggsi
"Cypraea boggsi" = Cypraeorbis boggsi Olsson 1928 cowry
 Heterostropha - Mathildidae
Tuba peruviana Olsson 1930 snail
 Dentaliida - Dentaliidae
Dentalium boggsi tusk shell